> ## Documentation Index
> Fetch the complete documentation index at: https://docs.anyfast.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# doubao-seed-evolving

> Creates a model response for the given chat conversation. Always routes to the latest Seed model (currently Doubao-Seed-2.1-Pro). Batch inference is not supported.



## OpenAPI

````yaml api-reference/model-api/bytedance/openapi/doubao-seed-evolving/openapi.yaml POST /v1/chat/completions
openapi: 3.1.0
info:
  title: Doubao Seed Evolving
  description: >-
    ByteDance's Doubao-Seed-Evolving model (always latest, weekly updates) via
    Anyfast OpenAI-compatible API
  version: 1.0.0
servers:
  - url: https://www.anyfast.ai
security:
  - bearerAuth: []
paths:
  /v1/chat/completions:
    post:
      summary: Chat Completion
      description: >-
        Creates a model response for the given chat conversation. Always routes
        to the latest Seed model (currently Doubao-Seed-2.1-Pro). Batch
        inference is not supported.
      operationId: createChatCompletionDoubaoSeedEvolving
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - model
                - messages
              properties:
                model:
                  type: string
                  enum:
                    - doubao-seed-evolving
                  description: Model ID
                  example: doubao-seed-evolving
                messages:
                  type: array
                  minItems: 1
                  description: A list of messages comprising the conversation so far.
                  items:
                    type: object
                    required:
                      - role
                      - content
                    properties:
                      role:
                        type: string
                        enum:
                          - system
                          - user
                          - assistant
                      content:
                        type: string
                  example:
                    - role: user
                      content: Hello!
                thinking:
                  type: object
                  description: Controls deep thinking. On by default for Doubao-Seed-2.1.
                  properties:
                    type:
                      type: string
                      enum:
                        - enabled
                        - disabled
                      default: enabled
                      description: Whether to enable chain-of-thought reasoning.
                reasoning_effort:
                  type: string
                  enum:
                    - minimal
                    - low
                    - medium
                    - high
                  default: high
                  description: >-
                    Controls reasoning length; effective only when thinking is
                    enabled.
                max_tokens:
                  type: integer
                  minimum: 1
                  maximum: 262144
                  default: 65536
                  description: The maximum number of tokens to generate (up to 256K).
                temperature:
                  type: number
                  minimum: 0
                  maximum: 2
                  default: 1
                  description: Sampling temperature. Higher values make output more random.
                  example: 1
                top_p:
                  type: number
                  minimum: 0
                  maximum: 1
                  default: 1
                  description: Nucleus sampling threshold.
                stream:
                  type: boolean
                  default: false
                  description: If true, stream partial message deltas using SSE.
                tools:
                  type: array
                  description: A list of tools (functions) the model may call.
                  items:
                    type: object
                response_format:
                  type: object
                  description: >-
                    Output format. Use { "type": "json_object" } for structured
                    JSON output (beta).
                  properties:
                    type:
                      type: string
                      enum:
                        - text
                        - json_object
                      default: text
                stop:
                  oneOf:
                    - type: string
                    - type: array
                      items:
                        type: string
                  description: >-
                    Sequences where the model will stop generating further
                    tokens.
      responses:
        '200':
          description: Completion generated successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ChatCompletion'
        '400':
          description: Invalid request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    ChatCompletion:
      type: object
      required:
        - id
        - object
        - created
        - model
        - choices
      properties:
        id:
          type: string
          example: chatcmpl-abc123
        object:
          type: string
          example: chat.completion
        created:
          type: integer
          description: Unix timestamp
        model:
          type: string
          example: doubao-seed-evolving
        choices:
          type: array
          items:
            type: object
            properties:
              index:
                type: integer
              message:
                type: object
                properties:
                  role:
                    type: string
                    example: assistant
                  content:
                    type: string
                    example: Hello! How can I help you today?
                  reasoning_content:
                    type: string
                    description: >-
                      Chain-of-thought summary, returned when thinking is
                      enabled.
              finish_reason:
                type: string
                enum:
                  - stop
                  - length
                  - tool_calls
                  - content_filter
                  - null
        usage:
          type: object
          properties:
            prompt_tokens:
              type: integer
            completion_tokens:
              type: integer
            prompt_tokens_details:
              type: object
              properties:
                cached_tokens:
                  type: integer
                  description: Number of cached tokens hit.
            total_tokens:
              type: integer
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            code:
              type: string
            message:
              type: string
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer

````